Campbell Scientific 109-L Temperature Probe - Manual (Page 19)

Model 109 Temperature Probe
8.3 Electrically Noisy Environments
EMF noise emanating from the ac mains power grid can be a significant source
of measurement error. 60 Hz noise is common in the United States. 50 Hz
noise is common in Europe and other regions. Depending on the datalogger
model, this noise can usually be filtered out.
The following code snips filter 60 Hz noise by placing the _60Hz argument in
the Integ/Fnotch parameter (in bold type).
For CR6 datalogger:
Therm109 (T109_C,1,U1,U10,20000,_60Hz,1.0,0.0)
For CR800, CR1000, CR3000, and CR5000 dataloggers:
Therm109 (T109_C,1,1,1,20000,_60Hz,1.0,0.0)
An integration parameter is not available for CR200(X) series dataloggers.
8.4 Long Cable Lengths
Long cable lengths may require longer than normal analog measurement
settling times. Settling times are increased by adding a measurement delay to a
datalogger program.
The 60 Hz and 50 Hz integration options include a 3 ms settling time; longer
settling times can be entered into the Settling Time parameter. The following
code snips increase settling time by 20000 µs by placing 20000 as the
argument in the SettlingTime parameter:
For CR6 datalogger:
Therm109 (T109_C,1,U1,U10,20000,_60Hz,1.0,0.0)
For CR800, CR1000, CR3000, and CR5000 dataloggers:
Therm109 (T109_C,1,1,1,20000,_60Hz,1.0,0.0)
A setting time parameter is not available for CR200(X) series dataloggers.
9. Troubleshooting and Maintenance
All factory repairs and recalibrations require a returned material
authorization (RMA) and completion of the “Declaration of
Hazardous Material and Decontamination” form. Refer to the
Assistance page at the beginning of this manual for more
information.
9.1 Troubleshooting
Symptom: Temperature is reported as NAN, –INF, or incorrect temperature.
Verify wire leads are connected to the terminals specified in the
Therm109() instruction: red to single-ended analog input (SE or U), black
to switched excitation ( VX/EX or U), and purple to ground ( ).
NOTE
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